1. Field of the Invention
The present invention relates to a backdoor system of a vehicle having a pressure sensor for detecting an object, which is pinched by a backdoor of the vehicle.
2. Description of Related Art
An automatic slide door system has been often used as a slide door system for opening and closing a side door opening arranged adjacent a rear seat of a vehicle, such as a wagon, a van, or a recreation vehicle. The automatic slide door system moves a door panel with a drive force of a motor or the like to open and close the side door opening.
In general, in the above described type of vehicle, a luggage room and a passenger room are not physically separated from each other, and a backdoor is provided at a rear opening of the vehicle. The backdoor is swung about a swing axis, which generally extends in a widthwise direction or lateral direction of the vehicle near a top end of the vehicle. By swinging the backdoor toward and away from the rear gate, the rear opening is closed and opened, respectively.
In such a backdoor system, the closing and opening operation of the backdoor has been manually conducted. When the rear opening is fully opened, the backdoor is raised to its top end position, so that the closing operation of the backdoor is bothersome, and thus it is desired to automatically operate the backdoor with driving force, such as of a motor, like in the case of the slide door.
In such an automatic backdoor system, it is conceivable to use a pinched object detection apparatus used in the automatic slide door system to detect the object pinched by the door.
In the pinched object detection apparatus of the automatic slide door system, a pressure sensor is arranged at a leading end portion of the door panel on the door opening side thereof. When an object is pinched between the closing door panel and an inner peripheral portion of the door opening, pressing force is applied to the object, which in turn, applies reaction force to the pressure sensor, resulting in detection of the reaction force by the pressure sensor.
In the backdoor system, two shock absorbing gas dampers are arranged at opposed lateral ends of the vehicle, respectively, between the rear gate and the backdoor to restrain rapid swing motion of the backdoor when the backdoor is swung toward the rear gate.
Each gas damper has a tubular cylinder (damper case) and a piston. One of the cylinder and the piston is pivotably connected to the rear gate, and the other one is pivotably connected to the backdoor.
When the backdoor is swung toward and away from the rear gate to close and open the rear opening, respectively, each gas damper pivots about the connection between the gas damper and the backdoor and also about the connection between the gas damper and the rear gate, and each piston is retracted into and extended from the cylinder, respectively.
When the backdoor is swung toward the rear gate, the object could be pinched between the backdoor and the vehicle body, as described above, and also could be pinched between the gas damper and the vehicle body. Depending on a location of the gas damper in its swing path, the gas damper could be positioned closer to the vehicle body than is the backdoor. In such a case, if the pinched object detection apparatus similar to that of the automatic slide door system is applied to the backdoor, it is difficult to detect the object pinched between the gas damper and the vehicle body.